In Corley′s algorithm for all efficient spanning trees, final solutions include many spanning trees, which are not all efficient. In this paper, a new algorithm is presented, which corrects and modifies Corley′s alg...In Corley′s algorithm for all efficient spanning trees, final solutions include many spanning trees, which are not all efficient. In this paper, a new algorithm is presented, which corrects and modifies Corley′s algorithm. A necessary condition is developed for the subtree of an efficient spanning tree. According to the condition the new algorithm is established and its efficiency is proved.展开更多
The present research is based upon a comprehensive survey which discusses the slightly tolerable water level of Balaton between 2000 and 2003. The low water level of the extreme period caused considerable problems in ...The present research is based upon a comprehensive survey which discusses the slightly tolerable water level of Balaton between 2000 and 2003. The low water level of the extreme period caused considerable problems in recreation. Our goal was to investigate the possible water transfer policies and the water level regulation policy of Lake Balaton by applying the dynamic programming of Markov chains. This iteration supports the cost-benefit analysis of different scenarios and also provides information about the best water governing policy. As a basis of our scientific analysis, Markov chains were created by ARMA （autoregressive moving average） synthetic data generator. Profit was joined to each transition-probability for the economic analysis. In our case the profit was negative, because the harmful effects of the low water level should be estimated, which is based on the calculated willingness-to-pay for improving the water quality of Lake Balaton. In addition, the profit includes the cost of different water supplement scenarios. After computer programming, the method proved to be an efficient tool to buttress the cost-benefit analysis of water supplement scenarios. The result highlights the importance of further climate change monitoring. Calculation confirmed water transfer to be cost-effective, yet scenarios with less ecological risk are also effective, thus preferable.展开更多
Crude oil distillation is important in refining industry. Operating variables of distillation process have a critical effect on product output value and energy consumption. However, the objectives of minimum energy co...Crude oil distillation is important in refining industry. Operating variables of distillation process have a critical effect on product output value and energy consumption. However, the objectives of minimum energy consumption and maximum product output value do not coordinate with each other and do not lead to the maximum economic benefit of a refinery. In this paper, a systematic optimization approach is proposed for the maximum annual economic benefit of an existing crude oil distillation system, considering product output value and energy consumption simultaneously. A shortcut model in Aspen Plus is used to describe the crude oil distillation and the pinch analysis is adopted to identify the target of energy recovery. The optimization is a nonlinear programming problem and solved by stochastic algorithm of particle warm optimization.展开更多
文摘In Corley′s algorithm for all efficient spanning trees, final solutions include many spanning trees, which are not all efficient. In this paper, a new algorithm is presented, which corrects and modifies Corley′s algorithm. A necessary condition is developed for the subtree of an efficient spanning tree. According to the condition the new algorithm is established and its efficiency is proved.
文摘The present research is based upon a comprehensive survey which discusses the slightly tolerable water level of Balaton between 2000 and 2003. The low water level of the extreme period caused considerable problems in recreation. Our goal was to investigate the possible water transfer policies and the water level regulation policy of Lake Balaton by applying the dynamic programming of Markov chains. This iteration supports the cost-benefit analysis of different scenarios and also provides information about the best water governing policy. As a basis of our scientific analysis, Markov chains were created by ARMA （autoregressive moving average） synthetic data generator. Profit was joined to each transition-probability for the economic analysis. In our case the profit was negative, because the harmful effects of the low water level should be estimated, which is based on the calculated willingness-to-pay for improving the water quality of Lake Balaton. In addition, the profit includes the cost of different water supplement scenarios. After computer programming, the method proved to be an efficient tool to buttress the cost-benefit analysis of water supplement scenarios. The result highlights the importance of further climate change monitoring. Calculation confirmed water transfer to be cost-effective, yet scenarios with less ecological risk are also effective, thus preferable.
基金Supported by the National Natural Science Foundation of China(21176178)the State Key Laboratory of Chemical Engineering(SKL-Ch E-13B02)
文摘Crude oil distillation is important in refining industry. Operating variables of distillation process have a critical effect on product output value and energy consumption. However, the objectives of minimum energy consumption and maximum product output value do not coordinate with each other and do not lead to the maximum economic benefit of a refinery. In this paper, a systematic optimization approach is proposed for the maximum annual economic benefit of an existing crude oil distillation system, considering product output value and energy consumption simultaneously. A shortcut model in Aspen Plus is used to describe the crude oil distillation and the pinch analysis is adopted to identify the target of energy recovery. The optimization is a nonlinear programming problem and solved by stochastic algorithm of particle warm optimization.
